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Keeping your powder dry!

8mmDale

Private
Full Member
Minuteman
My wife and I just bought a house and I immediately took over the basement for the new gun shop. The house had been vacant for almost a year so it had some mold and humidity problems in the basement. We got the mold taken care of, and with two humidifiers running, I think we have the humidity taken care of too. Do any of you guys monitor your basement, or the room you keep your reloading stuff in for humidity?? I turned on the kestrel when we first moved in and it was like 65%, now its down to about 55%. Im not really sure what it should be, but it no longer feels muggy down there. Its pretty pleasant. Im going to keep running the de-humidifiers until its DRY.

Any advice or knowledge? I keep my powder sealed up tight, but its still a worry I have about powder getting ruined now that its hard to find.
 
I also have my gun room in the basement. I keep my dehumidifier at 45%. I have never had a problem with moisture in my powder or primers. I keep my primers in an army ammo can j use in case though.
 
That would be an interesting question to ask the manufacturers of the powder: What is the optimum humidity level? Keeping your powder dry had a much greater meaning in the black powder days when the various parts of the mixture were water soluble. I understand that the makers of UNIQUE have a sample of that powder that is a hundred years old...they store it under water, and every once in a while take out a small part, dry it out and test it. From reports, it is just as good as when made. One thing with excess humidity...it could change the weight of a volumetric sample...i..e., 3 cc might weigh a grain or two more at high v/s low humidity. What effect that would have on your velocities or accuracy I couldn't guess.
 
If you have a "damp" basement, you will have greater problems than keeping your powder dry, like rusting dies and presses and such.

Keep the lids to your containers snug and you shouldn't have any problems. Powder doesn't readily absorb moisture.
 
My guns are kept in the home proper, where the environment keeps me and them both comfortable. My loading area is in the garage, with primers kept in a .30 caliber (not .50 caliber) ammo can, and powder in a 20mm ammo can; either of which is adequately suited to protect these items from humidity. While there is a temptation to maintain large stocks of primers and powder, I have so far managed to resist that urge. I also don't believe in storing handloaded ammo over the long term; I believe components weather time better in their separate state. I usually manage to avoid handloading work when the garage temperatures and humidity are outside a reasonable comfort zone; at my age, that mostly conforms to my shooting season anyway.

As a rule of thumb, I figure if I'm comfortable, it's OK to open up my powder and primer storage and make ammo. As above, if powder containers are good enough for interstate transportation, they should also be fine for indefinite storage.

Greg
 
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If the powder is sealed, humidity should not be an issue.
I believe the biggest issue with storing powder is the temperature it is stored at.

Primers on the other hand may need to have their humidity controlled being their package is not airtight-ish.
 
My wife and I just bought a house and I immediately took over the basement for the new gun shop. The house had been vacant for almost a year so it had some mold and humidity problems in the basement. We got the mold taken care of, and with two humidifiers running, I think we have the humidity taken care of too. Do any of you guys monitor your basement, or the room you keep your reloading stuff in for humidity?? I turned on the kestrel when we first moved in and it was like 65%, now its down to about 55%. Im not really sure what it should be, but it no longer feels muggy down there. Its pretty pleasant. Im going to keep running the de-humidifiers until its DRY.

Any advice or knowledge? I keep my powder sealed up tight, but its still a worry I have about powder getting ruined now that its hard to find.

I would think you are good around 50% humidity. Be careful about getting it too dry, you might induce a static electricity problem. That will mess with your electronic scales, could cause powder to hang up in things like your powder loading funnel, and worst case, if you by any chance happen to do anything with black powder, whoa!
 
I also have my gun room in the basement. I keep my dehumidifier at 45%. I have never had a problem with moisture in my powder or primers. I keep my primers in an army ammo can j use in case though.

Don't forget that primers are considered explosive! You shouldn't have any problems with humidity at 45%. I would keep them in the original packing material only. If for any reason, one went off in the ammo can and set the rest off (such as in a house fire) instead of having a bunch of pops spread out over time, you could have one large explosion. The ammo can would contain the quickly increased pressure until it failed catastrophically.

I know what you're thinking, did he fire six shots or... OOPS, different subject, back to the ammo can, it's made for storing ammo. Look at it this way, you don't have to pay a Hazmat fee to ship finished ammo, but you do for primers or powder. That indicates that someone thinks primers and powder are much more dangerous than finished rounds. Also, I keep hearing not to change containers for primers. Maybe the original container, stored inside an ammo can, will be enough to prevent a chain reaction, but in the words of Inspector Harry Callahan, You've got to ask yourself one question, Do I feel lucky?
 
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I actually had the opposite experience with powder. I inherited some IMR4895 in a new can (metal) that as best as I could tell was from the early 90's (about 20 years old). I loaded up some 168's up to 42 grains which should have been well below max, but I was getting flat primers and sticking bolt, and about 200 fps faster than I expected. I guess the powder actually dried out over time and caused there to be more powder per grain than fresh powder.


--Daniel
 
Don't forget that primers are considered explosive! You shouldn't have any problems with humidity at 45%. I would keep them in the original packing material only. If for any reason, one went off in the ammo can and set the rest off (such as in a house fire) instead of having a bunch of pops spread out over time, you could have one large explosion. The ammo can would contain the quickly increased pressure until it failed catastrophically.

I know what you're thinking, did he fire six shots or... OOPS, different subject, back to the ammo can, it's made for storing ammo. Look at it this way, you don't have to pay a Hazmat fee to ship finished ammo, but you do for primers or powder. That indicates that someone thinks primers and powder are much more dangerous than finished rounds. Also, I keep hearing not to change containers for primers. Maybe the original container, stored inside an ammo can, will be enough to prevent a chain reaction, but in the words of Inspector Harry Callahan, You've got to ask yourself one question, Do I feel lucky?

I will have to test this. I have tested 100 primers in the same package before and the majority of them went off at the same time. I know there is a reason powder is now put in plastic containers, so. The pressure can't build and it will just burn.

I guess i feel kinda lucky.
 
I would think you are good around 50% humidity. Be careful about getting it too dry, you might induce a static electricity problem. That will mess with your electronic scales, could cause powder to hang up in things like your powder loading funnel, and worst case, if you by any chance happen to do anything with black powder, whoa!

Real black is not particularly susceptible to static electricity, as far as going off is concerned.
 
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Real black is not particularly susceptible to static electricity, as far as going off is concerned.
I have to admit I have no personal experience with it. It just seems that EVERY tool I have says not to use it with black powder. I just figured that it was easy to ignite. So a static electric spark will not set it off? My bad.
 
I just keep my powders in a closet in my house, I would never store powder in an ammo can or other strongly constructed object due to the gasses not be able to vent if the powder happens to catch fire possibly causing an explosion...has it happened i don't know but i don't take chances.

here is a link with info, it's a PDF from Saami

http://www.saami.org/specifications.../download/SAAMI_ITEM_200-Smokeless_Powder.pdf
 
Smokeless Powders are deliberately coated with substances intended to retard ignition, thereby helping establish burn rates; as well as being electrically conductive (Carbon. Graphite, Charcoal, etc.) to equalize static electrical charges within a propellant mass preventing building up sufficient to allow a static discharge.

Physical Properties:

Smokeless powder may be corned into small spherical balls or extruded into cylinders or strips with many cross-sectional shapes (strips with various rectangular proportions, single or multi-hole cylinders, slotted cylinders) using solvents such as ether. These extrusions can be cut into short ('flakes') or long pieces ('cords' many inches long). Cannon powder has the largest pieces.

The properties of the propellant are greatly influenced by the size and shape of its pieces. The specific surface area of the propellant influences the speed of burning, and the size and shape of the particles determine the specific surface area. By manipulation of the shape it is possible to influence the burning rate and hence the rate at which pressure builds during combustion. Smokeless powder burns only on the surfaces of the pieces. Larger pieces burn more slowly, and the burn rate is further controlled by flame-deterrent coatings which retard burning slightly. The intent is to regulate the burn rate so that a more or less constant pressure is exerted on the propelled projectile as long as it is in the barrel so as to obtain the highest velocity. The perforations stabilize the burn rate because as the outside burns inward (thus shrinking the burning surface area) the inside is burning outward (thus increasing the burning surface area, but faster, so as to fill up the increasing volume of barrel presented by the departing projectile).[19] Fast-burning pistol powders are made by extruding shapes with more area such as flakes or by flattening the spherical granules. Drying is usually performed under a vacuum. The solvents are condensed and recycled. The granules are also coated with graphite to prevent static electricity sparks from causing undesired ignitions.[20]

Faster-burning propellants generate higher temperatures and higher pressures, however they also increase wear on gun barrels

This improvement is the single factor that makes it possible to ship firearm propellants safely and has been a staple of the industry for well over a century.

Traditionally, this has been graphite, which mostly fails to burn, and becomes the main component of carbon/powder fouling.

This fouling constitutes a dry bore lubricant. In some ways I personally believe this makes other dry lube strategies like Moly redundant, adding a layer of complexity to the bore friction equation that I'd rather just do without.

Scrupulous bore cleaning removes all traces of this bore lube, creating a copper/steel friction condition that imposes a higher drag on the bullet, leading to higher pressures. This is borne out by pressure/velocity deficits when moly is added. It is the clean bore which imposes the highest bore drag/pressure in a firing cycle, sometimes even leading to a cold/clean bore POI deviation. That's right; sometimes it is the gun.

I always leave a light coating of oil in a clean bore to alleviate this pressure condition. I sometimes suspect that treating the clean bore with a graphite prep might work even better. Some folks do it different with a Moly prep.

Greg
 
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powder and primers stored in an old fridge with desiccant. Doesn't matter if the fridge is working or not since it's not plugged in. I do this more for temp stability than humidity.
 
Static Electricity and Black Powder

There are a lot of "myths and legends" about black powder out there.

Careful handling is still a good idea!!

Wow, you could've knocked me down with a... I learned something there. That certainly doesn't seem intuitive. In fact, it reminds me of a Mythbusters episode where they disproved the myth about cell phones being able to ignite gasoline vapors. They even went to the extent of building a plexiglass enclosure (looked to be about 200 ft3) in which they developed a measured fuel/air mixture which was between the upper and lower explosive limits. As is usually the case on that show, when they couldn't get the cell phone to set it off, they introduced a positive ignition source and blew the enclosure apart.

update: To show just how pervasive that myth about sparks is, the link that peligro113 posts above shows that even SAAMI is misinformed considering that they are only talking about smokeless powder:
"Ignition occurs when the powder granules are heated above theirignition temperature. This can occur by exposing the powder to:1. A flame such as a match or a primer flash.​
2. An electrical spark or the sparks from welding, grinding, etc..."
 
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Wow, you could've knocked me down with a... I learned something there. That certainly doesn't seem intuitive. In fact, it reminds me of a Mythbusters episode where they disproved the myth about cell phones being able to ignite gasoline vapors. They even went to the extent of building a plexiglass enclosure (looked to be about 200 ft3) in which they developed a measured fuel/air mixture which was between the upper and lower explosive limits. As is usually the case on that show, when they couldn't get the cell phone to set it off, they introduced a positive ignition source and blew the enclosure apart.

update: To show just how pervasive that myth about sparks is, the link that peligro113 posts above shows that even SAAMI is misinformed considering that they are only talking about smokeless powder:
"Ignition occurs when the powder granules are heated above theirignition temperature. This can occur by exposing the powder to:1. A flame such as a match or a primer flash.​
2. An electrical spark or the sparks from welding, grinding, etc..."

Glad you found it useful, good luck
 
I'm in the great state of Wyoming where it is always DRY and distances are LONG. So I don't have to worry about it. :cool:
Thank God for the midwest! ND reporting here and everything stays well and dry here. 'Cept in springtime.
But I just keep my powder cans sealed and my primers in a container.
 
Unscrew the cap on your reloading propellant bottle or can. See that gasket material? As long as that gasket material contacts the ring on the can or bottle, with a modicum of compression, you're in good shape. Now, I'd not store my cans or bottles out in the elements. But, if you're in a basement or outdoor shed, or a non-working refrigerator outdoors, you're probably in fine shape.

Propellant being a plastic, should it ever get wet or damp, you CAN dry it out. Just stick it out in the sun on a warm day with low humidity. All that moisture will get driven off.

But remember, moisture acts as a burning rate modifier. If you set up a load with "damp" powder, and think the pressure fine, should you later shoot that same powder (yet, now dry), you'll encounter an entirely different animal.

So, the question of whether it matters if your powder is dry or not is a perfectly valid one. Be careful.